Improving the performance of HTTP over high bandwidth-delay product circuits

As the WWW continues to grow, providing adequate bandwidth to countries remote from the geographic and topological center of the network, such as those in the Asia/Pacific, becomes more and more difficult. To meet the growing traffic needs of the Internet some Network Service Providers are deploying satellite connections. Through discrete event simulation of a real HTTP workload with differing international architectures this paper is able to give guidance on the architecture that should be deployed for long distance, high capacity Internet links. We show that a significant increase in the time taken to fetch HTTP requests can be expected when traffic is moved from a long distance international terrestrial link to a satellite link. We then show several modifications to the network architecture that can be used to greatly improve the performance of a satellite link. These modifications include the use of an asymmetric satellite link, the multiplexing of multiple HTTP requests onto a single TCP connection and the use of HTTP1.1

Causality Violations in Cascade Models of Nuclear Collisions

Transport models have successfully described many aspects of intermediate energy heavy-ion collision dynamics. As the energies increase in these models to the ultrarelativistic regime, Lorentz covariance and causality are not strictly respected. The standard argument is that such effects are not important to final results; but they have not been seriously considered at high energies. We point out how and why these happen, how serious of a problem they may be and suggest ways of reducing or eliminating the undesirable effects.Comment: RevTeX, 23 pages, 9 (uuencoded) figures; to appear in Phys. Rev

Large Increase in Land Values in 1950

Iowa land values increased on average of 11 percent in 1950 over 1949-the largest single-year rise since 1920. Most of the rise came after hostilities began in Korea

Land Values Increased in 1951

Although total sales volume was down in 1951, Iowa land values rose an average of $15 per acre in 1951- boosting them to a level exceeded only in two previous years, 1920 and 1921

Iowa Farm Values Up Again!

Iowa farm land values increased an average 3 1/2 percent in the year ending Nov. 1, 1954. The state average on that date was $205 per acre-$7 above the average of a year earlier

How Much is Your Farm Worth?

It\u27s often necessary to estimate the approximate market value of a given farm-either for the present time or for some year in the past. Here\u27s some information to help you do this without great trouble or expense

Farm Land Values Dip 5 Percent

Iowa farm land values dropped an average of 5 percent during the year ending Nov. 1, 1953. Analysis of reports from 389 farm real estate brokers representing all counties in the state showed that all regions of the state were affected by the decline and that low-quality land dropped the most. Major farm land value developments during the year were

Land Price Rise Slows Down

Iowa land prices continued to rise during 1948, but at a slower rate. Excellent grades of land rose more than fair to poor grades. Also, fewer sales were reported for 1948 than during the previous year

Little Change in Land Values in 1949

Farm land values in Iowa increased only $1 an acre in 1949. They rose from$176 to $177 an acre, accroding to reports from 537 real estate brokers. Values actually declined a little in southern, western and eastern areas of the state. But these declines were more than offset by increases in the two northern areas

Memory-Controlled Diffusion

Memory effects require for their incorporation into random-walk models an extension of the conventional equations. The linear Fokker-Planck equation for the probability density $p(\vec r, t)$ is generalized to include non-linear and non-local spatial-temporal memory effects. The realization of the memory kernels are restricted due the conservation of the basic quantity $p$. A general criteria is given for the existence of stationary solutions. In case the memory kernel depends on $p$ polynomially the transport is prevented. Owing to the delay effects a finite amount of particles remains localized and the further transport is terminated. For diffusion with non-linear memory effects we find an exact solution in the long-time limit. Although the mean square displacement shows diffusive behavior, higher order cumulants exhibits differences to diffusion and they depend on the memory strength